Yes, we already weren't doing terribly as far as saving and investing goes. We bought the house when only I had a job (and he was going to school with the GI Bill) so the bank would only give us a loan based on my salary (a number which we made the mistake of just about maxing out), but for the past couple of years we've both had similar-salary jobs leaving lots of room for saving.
We currently have almost $300K between 401ks, TSPs, and stocks/funds/CDs/REITs/P2P-lending investments. (Unfortunately the non-retirement investments are not too impressive yet as far as growth and interest/dividend yields since we only recently found the courage to venture out of the giant cash cushion/mutual funds & CDs mentality.)
I have my 401k maxed out with 6% matching from my employer and now that I've slashed down "latte factor" and "lady temptations" spending plus things like cell phone, internet, and insurance bills, I have half my net paycheck going into my savings account (with the intent of dumping more into my non-retirement investments by the quarter) and the other half going into checking (to cover daycare, gas, utilities, and groceries/toiletries/baby & kitty supplies). My husband allots 10% to his 401k with 10% matching, most of his Reserves payments into his TSP, recently dumped a lot of his spare cash into stocks and funds, with most of his remaining income covering the mortgage.
Since we have no other debt, I guess he views paying down the mortgage as a form of diversification. And since we can't actually predict whether or not we'll still be here in 5 or 10 years or indefinitely, with all those other investments there's probably not a big need to push my husband against that extra money to the mortgage. (Especially considering ERE's "death-grip ripoff" view on mortgages.) With our hope of retiring in 5-10 years, I suppose the relative stability of paying down a 3.25% mortgage faster helps balance out stocks for such a short term goal.
On the other hand, having become a bit obsessive about FI the question will continue to toss around in my head. ;)